Embodiments of the present invention relate to an ultrasound imaging technique, more particularly to a method, apparatus and system for enhancing needle visualization in medical ultrasound imaging at different scanning depths.
In medical device ultrasound guidance application, the needle visualization in ultrasound image is paramount for the clinician to successfully perform an invasive ultrasound image guided procedure.
Needle visualization techniques in medical ultrasound systems, such as B steer, SteerXBeam and Expanded SteerXBeam, usually use one special additional frame called “needle frame” with fixed big steering angle and collected by applying fixed ultrasound working frequency to visualize and enhance the needle. If the needle guidance direction is vertical to the steering angle for needle frame, needle visualization is enhanced. Otherwise, the needle will disappear or fade in the ultrasound image.
For example, the U.S. Pat. No. 6,524,247 entitled “Method and system for ultrasound imaging of a biopsy needle” filed by Danhua Zhao et al. on May 15, 2001 discloses a method for enhancing real time visualization of a puncture needle, said method using a fixed scan angle (or a needle frame steering angle) to collect a needle frame. The Chinese patent application No. 201010624654.3 entitled “Method and apparatus for enhancing needle visualization in ultrasound imaging” filed by Jianjun Guo et al. on Dec. 27, 2010 discloses a needle frame with a large steering angle (e.g., 45°) and teaches that a plurality of frames collected by scanning at multiple angles, e.g., 25° and 45°, are combined to yield a needle frame, thereby achieving optimum effect.
However, as patients differ greatly in figures, the same parts or tissues (e.g., heart) have different scanning depths in different patients, and different parts or tissues have different scanning depths in the same patient as well. In the above-mentioned prior art, a fixed needle frame steering angle is always used for ultrasound scanning at different scanning depths, regardless of depth differences of different scanned parts or tissues in patients. As a result, when the fixed needle frame steering angle is used to scan a large (e.g. obese) patient, the needle is inserted into the patient's body substantially vertical to skin, such that the needle keeps substantially parallel to ultrasonic beam, thereby causing the needle to disappear or fade in the ultrasound image. Hence, the needle frame collected with fixed needle frame steering angle and ultrasound working frequency in the prior art cannot satisfy ultrasound guidance requirements at different depths.
Thus, it is necessary to provide a method, apparatus and system to avoid the aforesaid problems and defects.